Performance of in-vessel composting of food waste in the presence of coal ash and uric acid

• Published in: Journal of hazardous materials Vol. 203; pp. 38 - 45
• Main Authors: An, Chun-Jiang, Huang, Guo-He, Yao, Yao, Sun, Wei, An, Kai
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 15.02.2012
• Subjects: Ashes; Coal; Coal ash; Composting; Food; Food waste; Foods; Hydrogen-Ion Concentration; In-vessel system; industrial wastes; Microorganisms; oxygen; Oxygen - chemistry; Reactors; Soil; Temperature; Uric acid; Uric Acid - chemistry; Wastes; Food waste; Composting; Uric acid; In-vessel system; Coal ash
• ISSN: 0304-3894; 1873-3336
• DOI: 10.1016/j.jhazmat.2011.11.066

► The amendments of CA and UA could facilitate the composting performance. ► The overall performance is a sum of different events with different mechanisms. ► The added CA and UA might lead to higher pH during the composting. ► The process is correlated with the variations of microbial activity and C/N ratio. ► The presence of CA and UA has significant influence on composting of food waste. Massive quantities of food waste often coexist with other agroindustrial and industrial waste, which might contain coal ash (CA) and uric acid (UA). This study investigated the influence of CA and UA on the composting of food waste in the in-vessel system. The patterns of food waste composting were compared among various combinations. The results showed that the temperature level was enhanced in the presence of CA and UA during the first 8 days. The significant drop in pH was observed in the treatment without any amendment. But the presence of CA could alleviate the drop of pH. More intensive organic mass reduction took place in the treatments with amended CA and UA in the first half of process. The O 2 uptake rate in the reactor with CA and UA was higher than that with only CA in the early stage. Both thermophilic and mesophilic microorganisms were present throughout the composting period. The populations of both thermophilic and mesophilic microorganisms were influenced when amended with CA and UA. The decreasing trend in C/N ratio was shown in all the reactors, while a relatively lower C/N ratio was obtained in the series with both CA and UA.